Abstract
Purpose: :
To investigate the architecture of filtering blebs and the relation to bleb leaks by in vivo laser confocal microscopy after trabeculectomy with or without antiproliferatives.Patients:17 eyes of 12 patients (8 males, 4 females) with functioning blebs in whom the intraocular pressure was under 20mmHg were included in this study.
Methods: :
After a detailed slit-lamp examination including Seidel test, we examined the filtering blebs by in vivo confocal microscopy (Rostock Cornea Module/Heidelberg Retina Tomograph 2). The details of surgical procedures and medications and clinical course of each patient was recorded in detail.
Results: :
17 eyes of 12 patients were examined 2 months to 170 month after final trabeculectomy (mean 72 months). The final surgical procedures included trabeculectomy with mitomycin-C (13 eyes), trabeculectomy with 5-FU (3 eyes), and trabeculectomy without antiproliferatives (1 eye). There were 8 leaking blebs all of which had a positive Seidel test (Group 1). Other 9 eyes had no bleb leaks (Group 2). The duration of each group after final surgery was 86.4+/-70.8 month in Group 1, 46.6+/-70.5 month in Group2. The difference between two groupes was not statistically significant. In vivo confocal microscopy showed 20-50µm microcysts in the structure and vicinity of the wall of all filtering blebs, an observation which was significantly frequent in Group 1 (density of microcysts : 10.5+/-5.4 per 0.16mm2) than the non-leaking blebs (density of microcysts : 2.5+/-2.1 per 0.16mm2)(p<0.01). Conjunctival epithelial density was 2025+/-704 cells/mm2 in Group 1, 3190+/-1028/mm2 in Group 2. The difference was statistically significant (p<0.01). No adverse events were observed due to in-vivo scanning in this study.
Discussion: :
In vivo confocal microscopy was a safe and an efficient method to investigate the structure of filtering blebs. Density of microcysts in blebs and the conjunctival epithelial density may be important in relation to pathogenesis of bleb leakage.
Keywords: pathology: human • wound healing • imaging/image analysis: clinical